Inactive behaviors are characterized by lack of motion, unlike active behaviors which are defined by the presence of motion.
A mouse can be inactive either during wakefulness or while sleeping. Inactive behaviors can occur in isolation (such as sleeping) or within a behavioral sequence which already contains active behaviors.
To illustrate the latter, in an agonistic encounter typically characterized by active behaviors, a mouse may retreat and hide. So, active behaviors (running away and retreating) may be interlaced with inactive behaviors (hiding).
Inactive behaviors are crucial for restoring energy levels. For example, sleeping is an inactive behavior which is also a maintenance behavior that is crucial for keeping the mouse healthy and its internal energy levels in homeostasis.